A Big Island man has become the second person in less than two weeks to die while free diving in Hawai'i waters.

Bradford Ordell of Kona died Wednesday at North Hawai'i Community Hospital in Waimea, three days after he was pulled unconscious from the waters of Kiholo Bay, Big Island police said.

Ordell, 28, was free diving in a fresh water pond in an underwater lava tube about 10:30 a.m. Sunday when he failed to surface. A diving companion searched for him and found him in about 15 feet of water.

Ordell's unconscious body was brought to shore where Hawai'i County Fire Department rescuers tried to review him and then took him to the hospital.

An autopsy determined that Ordell drowned, police said.

On July 24, Gene Higa, an accomplished diver with more than two decades of experience, was found dead after he failed to return from a dive on O'ahu's North Shore.

Higa, who had won one national championship, was competing in the U.S. National Spearfishing Championships when he died.

After Higa's death, Al Lagunte, president for North Shore Fishers and coordinator of the national championships in Hale'iwa, said he knew of three other deaths related to free diving on O'ahu this year alone.

An autopsy revealed that Higa drowned, the Honolulu medical examiner's office said yesterday.

Although details of what happened to Higa aren't known, Lagunte said a condition called shallow water blackout has led to the deaths of a number of free divers in recent years.

The blackouts, caused by oxygen deprivation, generally occur during the end of a dive, and most often when the diver, reaching the end of his endurance, is distracted by a fish or tangled equipment and delays surfacing, said Bill Ernst, director of skin diving for the Underwater Society of America.

Following Higa's death, both Lagunte and Ernst said something must be done to make free diving safer. They said they planned to discuss going to two-man teams in U.S. competition.